Mitosis

• Why do multicellular eukaryotic organisms require new cells?

  They require new cells for growth, development, and repair.
• What is the process through which new cells are generated called?

  The process is known as the cell cycle.
• What are the three main stages of the cell cycle?

  • Growth
  • DNA replication
  • Mitosis and division (cytokinesis)
• What happens during the growth stage of the cell cycle?

  The cell grows in size and increases the number of subcellular structures.
• What occurs during DNA replication in the cell cycle?

  The DNA is duplicated so that each new cell has a full set of DNA.
• How does DNA appear when a cell is not dividing?

  DNA is spread out in long strings.
• What happens to DNA when a cell prepares for division?

  The DNA condenses into chromosomes.
• What are chromosomes?

  Chromosomes are packets of condensed DNA.
• How many copies of each chromosome do eukaryotic cells have?

  Eukaryotic cells have two copies of each chromosome, known as a pair.
• How many pairs of chromosomes do humans have?

  Humans have 23 pairs of chromosomes.
• Why can't animals of different species reproduce fertile offspring?

  Different species have different numbers of chromosomes.
• What happens to each chromosome during cell division?

  Each chromosome duplicates and stays attached to its original chromosome, forming an X shape.
• What do the arms of the X-shaped chromosomes represent?

  The arms represent duplicates of the original chromosome.
• What happens to the chromosomes during the division stage?

  All chromosomes line up along the center of the cell and are pulled to opposite sides.
• What is cytokinesis?

  Cytokinesis is the division of the cell membrane and cytoplasm to form two daughter cells.
• What do the resulting daughter cells contribute to after division?

  The daughter cells contribute to growth, development, or repair.
• What is the overall process of cell division in multicellular eukaryotic organisms?

  1. Cells grow and increase subcellular structures.
  2. DNA is replicated.
  3. DNA condenses into chromosomes.
  4. Chromosomes line up and are pulled apart.
  5. Cytokinesis occurs, forming two identical daughter cells.